Pressure cap for sealed cooling system



Nov. 9, 1965 M. D. MCCORMICK 3,216,608

PRESSURE CAP FOR SEALED COOLING SYSTEM Filed Sept. 12, 1963 2Sheets-Sheet 1 &

r ATT Nov. 9, 1965 M. D. M CORMICK PRESSURE CAP FOR SEALED COOLINGSYSTEM 2 Sheets-Sheet 2 Filed Sept. 12, 1963 a 3 1 //w Ham 0, 9 M .f i Fa 7 0 t w/ I a a a w 0. 2 a; 7 z .2 w w G 6 m H Wu F mi Fl 2 FIG. /0 2052 20 5 lNVENTpR. fiaazzbeflfi g omzc BY "A TTZRNEYS United States PatentOffice 3,21%,fifi3 Patented Nov. 9, 1965 3,216,608 PRESSURE CAP FORSEALED COOLING SYSTEM Maurice D. McCormick, Prospect Heights, 111.,assignor to The Dole Valve Company, Morton Grove, Ill., a corporation ofHlinois Filed Sept. 12, 1963, Ser. No. 308,438 11 Claims. (Cl. 22044)The present invention relates to a pressure closure cap structure andmore particularly to a cap for a radiator and associated coolant systemon an internal combustion engine. The cap is provided with means formaintaining pressure within the container or radiator within relativelynarrow upper and lower limits.

The present invention provides an improved closure cap structure ofsimple, economical, eflicient construction which vents excessivepressures within the system to a surge tank in order to maintain thedesired pressure condition within the system. According to the presentinvention, the cap preferably comprises a casting having an exhaustnipple formed on its side wall through which excessive pressures may bevented from the oppositely acting vent valves provided on the cap. Inthe past, an overflow tube has been mounted on the radiator incommunication with the tubular filling neck enabling pressures to bedischarged through the cap and neck into the overflow tube.

As noted above, according to important features of the presentinvention, an over-flow exhaust nipple is provided on the cap itselfthat is connected with a vented surge tank having a fluid level so thatthe excessive pressures are discharged directly from the cap toatmosphere rather than through an overflow tube welded to the radiatorhaving an inlet on the radiator neck.

An important object of the present invention is to provide a new andimproved closure cap structure having a nipple formed thereon forventing excessive pressure passing from the radiator to the cap throughthe cap nipple to a surge tank.

A further object of the present invention is to provide an improvedradiator cap structure having pressure relief means operable at variablepredetermined pressures.

The internal structure of the cap or casting includes a pressure valveor diaphragm resiliently urged to seated position to close the containeror radiator aperture on its neck, the valve or diaphragm being capableof being biased to an open position by excessive pressure developedwithin the radiator. The means for resiliently urging the diaphragm toseated position are capable of adjustment through a relatively widerange so that the pressures effective to bias the diaphragm to openposition may be likewise varied. A second, oppositely actuatingauxiliary valve is provided on the diaphragm to allow fluid to flow froma surge tank to the radiator as the fluid in the radiator cools.

An important object of this invention is to provide a new and improvedauxiliary vent valve having an auxiliary vent valve member which may besnapped into assembly with the biased diaphragm.

Still another important object of this invention is to provide animproved radiator cap structure which, when assembled on a vehicleradiator, will permit the overall system to be operated for prolongedperiods without the necessity of refilling the radiator with fluid.

Other ob ects and features of this invention will more fully becomeapparent in view of the following detailed description taken inconjunction with the accompanying drawings and illustrating severalembodiments, and in which:

FIGURE 1 is a top plan view of a radiator having a radiator capstructure embodying important features of the present invention mountedthereon;

FIGURE 2 is a vertical section taken substantially on the line IIIIlooking in the direction indicated by the arrows as shown in FIGURE 1;

FIGURE 3 is an enlarged fragmentary edge View partially in section takenon the line III-III looking in the direction indicated by the arrows asshown in FIGURE 1;

FIGURE 4 is a fragmentary view partially in section showing a modifiedtype of diaphragm and auxiliary valve;

FIGURE 5 is an enlarged vertical section of a modified type of radiatorcap structure mounted on a filler neck of a radiator;

FIGURE 6 is an enlarged vertical section similar to FIGURE 5 onlyillustrating the valves in open positions;

FIGURE 7 is an enlarged fragmentary partially sectioned top plan view ofa modified type of a radiator filler neck;

FIGURE 8 is an enlarged fragmentary partially sectioned side elevationof the filler neck shown in FIG URE 7;

'FIGURE 9 is an enlarged fragmentary partially sectioned viewillustrating the relationship between a locking tab and a ring; and

FIGURE 10 is an enlarged fragmentary edge View as taken on the line X-Xlooking in the direction indicated by the arrows as seen in FIGURE 7.

As shown on the drawings:

The reference numeral 10 indicates generally the top wall of a radiatorfor an internal combustion type engine having a tubular filling neck 11mounted thereon. According to the important features of this invention,a new and improved type of radiator cap structure 12 is mounted on theneck 11 of the radiator 10.

The cap structure 12 includes a cup-shaped cap or cast ing 13 defining acup 13a. The cup or casting 13a has a cup or casting bottom 14 and a cupor casting side wall 15. Projecting radially from the side wall 15 is afluid overflow nipple or vent 16. In the past, it has been the practiceto provide the overflow tube on the filler neck 11, but according to theimportant features of this invention, this overflow tube on the fillerneck can be eliminated by the provision of a nipple or vent 16 on thecap or casting 13.

Mounted within the cup 13a is a compression spring 17. The side wall orinner wall surface 15 is provided with a shoulder 18 and a ring-shapeddiaphragm is seated on the spring -17 and has its outer margin disposedopposite the shoulder 18. As illustrated, the diaphragm 19 is comprisedof a diaphragm back-up ring 20 having an angled outer margin 20adisposed opposite the shoulder 18. A ring-shaped diaphragm gasket 21comprised of any suitable material such as a rubber synthetic plastic orthe like, is provided for assembly with the metallic back-up ring orback-up member 207 A lock ring 22 is provided for assembly with theinside wall or surface 15 of the cup 13a in order to secure thediaphragm 19 with the casting 13. The lock ring 22 is spaced from theshoulder 18 and the outer margin 20a of the back-up ring is disposed inthe space therebetween. The relationship of the lock ring 22 withrespect to the outer margin 20a and the shoulder 18 is such that fluidcan flow between the outer margin 20a and the lock ring and between theouter margin 20a and the shoulder 18. It will further be noted that whenthe diaphragm 19 is seated on the filler neck seat 11a, the outer ringmargin 20a is spaced from the lock ring 22. When the diaphragm 19 isunseated with respect to the seat 11a, the outer margin 20a is spacedfrom the shoulder 18 to permit fluid flow through the gap therebetween.

In order to secure the back-up ring 20 with the gasket 21, the gasket 21is provided with a gasket collar 23 having a diaphragm gasket collargroove 24. The dia- ,phragm back-up ring has a collar or inner marginretainingly secured within the groove 24.

An auxiliary vent valve member 26 is mounted on the diaphragm 19 and isprovided with a shank 26a disposed inside gasket collar opening 23a. Theauxiliary vent valve member 26 further has an auxiliary valve closureflange or base portion 26b for seating on the annular pointed ribdefining gasket seat 28. A wobble pin 27 is mounted on shank 26a for thepurpose of suspending the auxiliary vent Valve member 26 from thediaphragm gasket collar 23. Upon cooling of the radiator 10, theauxiliary vent valve 26 will be unseated from the gasket seat 28 to.permit fluid to flow from the surge tank through nipple 16 back to theradiator.

Lugs 29 are provided on an outside or exterior wall or surface 30 of thecasting 13. A sealing gasket 31 is mounted in a gasket groove 32 formedon the exterior wall surface 36 in order to secure the sealing gasket 31in unitary assembly with the cup or casting 13.

The filler neck 11 has a pair of lug receiving grooves 34 spacedcircumferentially of one another which grooves are each provided with asafety vent notched shoulder 35 and a notched lock shoulder 36. When thecap structure 12 is to be assembled with the filler neck 11, the lugs 29are aligned with the filler neck grooves and then engage-d therein. Upontwisting of the cap structure, the lugs are cammed along the filler neckcam surfaces 34a until the lugs are engaged behind the lock shoulders36. This cam action allows the gasket 31 to be compressed against thefiller neck 11 to provid a seal between the cap structure 12 and thefiller neck 11. When the cap structure 12 is to be removed from thefiller neck 11, the cap structure 12 is rotated in opposite directionsand the lugs 36 are initially engaged against the safety vent notch orshoulder 35. When the lugs are engaged against the shoulder 35, thediaphragm 19 is unseated from part 11a but gasket 31 is not unseatedfrom the filler neck 11 and pressurized fluid within the radiator isthen allowed to escape through nipple 16 to the surge tank to relievefluid pressure within the radiator prior to complete removal of the captherefrom. The cap structure 12 may be rotated to disengage the lugs 28from the safety vent notched shoulders 35 and from the grooves 34 toremove the cap structure 12 from assembly with the filler neck 11.

The nipple 16 is communicable with a surge tank T which is, itself,vented to the atmosphere and which has at all times, liquid containedtherein, the level of which is at all times above the level of anyliquid contained within the cap itself. Thus, when water within theradiator is cooling, there will be a reverse flow from the surge tank Tto the radiator and the auxiliary valve member 26 will be open as shownin FIGURE 2. A the temperature of liquid Within the radiator begins torise, the auxiliary valve 26 will seat upon the resilient valve member19; then when the force of pressure of liquid acting on the underSurfaCeof the resilient valve member 19 equals or exceeds the opposingdownwardly directed force of pressure acting on the upper surfacethereof, the valve member 19 will be unseated from the filler neck seat11a and permit a flow of liquid from the radiator through the gapbetween lock ring 22 and an outer margin 2% of the back-up ring 20,which fluid will then flow to the surge tank T causing a rise in liquidlevel therein with no loss of liquid to the atmosphere. By the use ofthe surge tank T, the volume and pressure of fluid in the radiator maybe maintained at a constant level and liquid loss may be prevented. Byproviding a closed radiator fluid pressure system, it is no longernecessary for the operator to fill the radiator inasmuch as coolantexpansion is absorbed in the surge tank.

Shown in FIGURE 4 is a modified type of ring-shaped diaphragm 119 which,if desired, can be substituted in place of the diaphragm 19 shown inFIGURE *2. The diaphragm 119 includes a ring-shaped back-up ring 120 anda ring-shaped diaphragm gasket 121 which is secured by glue of anysuitable type to the underside of the ring 123. The ring has a flangeturned away from the ring to provide a collar 125 and a new and improvedauxiliary valve member 126 embodying important features of thisinvention is mounted on the collar 125. The auxiliary vent valve member26 is preferably fabricated from a high temperature memory type plasticsuch as Delrin, Teflon, or the like.

The auxiliary vent valve member 126 has a series of hook-shapeddeflectable prongs engaged in snap-on engagement with the collar 125.Preferably, a pair of the prongs 127 are mounted on an auxiliary ventvalve base 128. The base 128 has a V-shaped circumferential rib 129 forengagement with the gasket 121 when the valve is closed.

The valve member 126 can be more readily assembled with the diaphragm119 than prio types of valve members since assembly may be effectedmerely by pushing the prongs into the opening defined by the collar 125causing the prongs to collapse and snap back over the collar after thehooked ends are extended through the collar opening. This type of valvemember eliminates all possibility of leakage as encountered in priortypes of vent valves, and can be easily replaced if damaged. Also, thevalve member can be economically produced at less cost than conventionaltypes of vent valve members.

In FIGURE 5 is shown another modification and primed reference numeralshave been empl yed to identify parts which correspond to the partspreviously described in connection with the forms shown in FIG- URES l3.To this end, the reference numeral 10' indicates generally a radiatorhaving a neck 11' and a closure cap structure 12 mounted thereon.

The closure cap structure includes a cup or casting 13' having a bottom14 and a side wall 15. A nipple 16' extends radially outwardly of theside wall 15' and is disposed in spaced relation above the neck 11. Thenipple 16' is adapted for connection with a surge tank (not shown) inthe same manner as previously described in connection with the cap shownin FIGURE 3.

Mounted within the casting 13 is a spring 17'. The wall 15 further hasan axially facing shoulder 18' and a spring biased diaphragm or valvemember 19 is mounted within the cup opposite the shoulder 18'.

The diaphragm or valve member 19' includes a metal diaphragm ring 20 anda diaphragm gasket ring 21'. The rings 20' and 21' are secured togetherby means of a metal bushing 100 at the inner margins of the rings. Thebushing 100 holds the rings in snug engaged relation together.

A look ring 22 is secured with the inside wall surface of the wall 15'for holding the valve member or diaphragm 19' in assembly with thecastings 13. The casting may be manufactured from any suitable materialsuch as aluminum. In this instance, the ring 22 is engaged with a wallportion 101 having a larger diameter than the Wall 15'.

The diaphragm or valve member 19 is provided with an auxiliary valvemember 26 which includes an auxiliary valve body 26a suspended Withinthe diaphragm opening from its upper end. The auxiliary valve member 26further includes an auxiliary valve head 26]) which is riveted at 260 tothe valve body 26a. The valve head 26b, as shown in FIGURES 5 and 6,operates in much the same manner as the valve head 26b, as previouslydescribed. In summary, when water within the radiator is cooling, therewill be a reverse flow from the surge tank to the radiator and theauxiliary valve member will be in the position shown in FIGURE 5. As thetemperature of liquid within the radiator rises, the auxiliary head Willseat upon the resilient valve member 19. When the pressure differentialacross valve member 19 provides a net upward force, the valve member 19will be unseated from the filler neck seat to permit the liquid to flowfrom the radiator to the surge tank.

In order to mount the cap structure 12 upon the neck 11', the casting13' is provided with an annular flange 102 and a retainer ring orring-shaped cap 103 is mounted on the casting flange 102. The ring orcap 103 includes a radial ring or cap portion 103a and an axial ring orcap portion 10311. A series of slots 103a is formed in the annular axialring or cap flange 1031).

The filler neck 11 has radially outwardly extending neck tabs 11b. Toassemble the cap structure 12' with the neck 11, filler neck tabs 1112are axially aligned between the ring slots 103s whereupon the ring 103is rotated to cam the thus engaged tabs 11a in the slots 103c intoretained assembly therewith. It is in this way that sealing gasket 31 isplaced under pressure to seal the casting or cup 13' in assembly withthe neck 11.

The operation of the valve members 19 and 26 is the same as previouslydescribed in connection with the cap structure disclosed in FIGURE 2. Inthis regard, it will be noted that when the fluid pressure in theradiator is increased, the valve member 19' is unseated to permit thefluid to flow past a valve seat 11a and out through the nipple 16' tothe surge tank (not shown).

When the cap is rotated to a safety vent position the parts of theassembly will be disposed in the position shown in FIGURE 6.

In FIGURES 7-10 another modification is illustrated. This modificationis primarily concerned with the manner in which a radiator cap 200 issecured with a radiator and more particularly to a filler neck 201. Thecap 200 may be of any suitable type such as shown in FIG- URE l or asshown in FIGURE 5. It is intended that the cap 200 differ from thepreviously described caps in the manner in which the cap is secured withthe radiator. To this end, the radiator cap 200 is provided with threelugs 202 (only two of which are shown). The filler neck 201 has a pairof lug receiving grooves 203 such as is shown in FIGURE 10. When thelugs 202 are engaged in the grooves 203, such lugs can be moved intoengagement with safety vent notched shoulder 204 and a notched lockshoulder 205. The grooves 203 and the shoulders 204 and 205 are adaptedto coact with the lugs 202 in much the same manner as previouslydescribed in connection with the operation of the lugs 29 in the lugreceiving grooves 34.

The primary difference between the operation of the cap 200 and thepreviously described caps is that the filler neck 201 is provided with arectangularly configurated lug receiving slot 207 (FIGURE 8). One sideof the slot 207 is expanded to provide elongated slot portions 208, 208which are separated by a deflectable lock finger 209.

The cap 200 may be assembled on the filler neck 201 by engaging the lugs202 in the grooves 203 and by turning the cap until the lugs are engagedwith the shoulders 205 at which time the third lug 202 is engaged in theslot 208. Thereafter, the finger 209 is deformed and pressed inwardly sothat its free end 209a circumferentially opposes the lug 202 to preventremoval of the cap from the filler neck. It is in this way that the cap200 may be secured in permanent assembly with the filler neck 201. Itwill be appreciated that it is desirable to secure the cap in permanentassembly with the filler neck 201 in some assemblies so that a personwill not remove the cap from the filler neck for the purpose ofrefilling the radiator. Where a closed filling system is provided,including a surge tank as is shown in FIGURE 1, it is not necessary tocheck the radiator fluid level in accordance with the practicespreviously followed. 7

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon, all such modifications as reasonably andproperly come within the scope of my contribution to the art.

I claim as my invention:

1. In combination, a closure cap structure and an internal combustionengine radiator having a tubular filling neck with the closure capstructure thereon,

said cap structure including a generally cup-shaped cap itself having afiuid nipple extending outwardly from its side wall in overlying spacedrelation above said neck,

a vented surge tank connected with said fluid nipple having fluidoverlying the radiator,

an annular cup shoulder at an open end of the cupshaped cap,

a spring disposed inside of the cup defined by said cap,

a back-up diaphragm ring engaged on its top side with said spring andhaving a diaphragm gasket on its underside for movement with saidback-up diaphragm ring into and out of engagement with the tubularfilling neck,

a lock ring secured with the side Wall defining the open end of said capaxially spaced from said cap shoulder with said back-up ring and saiddiaphragm gasket being movable axially between said diaphragm ring andsaid cap shoulder upon the development of excessive pressure in theradiator suflicient to cause un-seating of said diaphragm gasket fromsaid filling neck permitting fluid flow between the outer margin of saidback-up diaphragm ring and the side Wall of the cup into the cup andthen through said fluid nipple into said surge tank,

said lock ring providing means securing said diaphragm gasket inintegral assembly with said cap to permit the cap, spring, diaphragmring and diaphragm gasket to be engaged on and removed from a fillingneck seat as a unit,

an auxiliary valve member mounted on said back-up diaphragm ring andsaid diaphragm gasket adapted to open when the fluid in the radiator iscooling permitting fiuid flow from the surge tank to the radiator, and

means on said cup-shaped cap securing the cap in sealed assembly withthe tubular filling neck of said radiator.

2. In a closure cap structure for attachment to a tubular filling neckfor an internal combustion engine radiator,

a generally cup-shaped cap itself having a fluid nipple extendingoutwardly from its side wall,

a vented surge tank connected with said fluid nipple having fluidoverlying the radiator,

an annular cup shoulder at an open end of the cupshaped cap,

a spring disposed inside of the cup defined by said cup-shaped cap,

a back-up ring mounted in the cup having an outer ring margin spacedfrom the side Wall and axially confronting said cup shoulder with saidspring engaged against said ring and with said ring having a gasket onits underside for engagement with a tubular filling neck,

a lock ring secured with the open end of said cap axially spaced fromsaid cap shoulder with said back-up ring and said gasket being movableaxially between said ring and said cap shoulder upon the development ofexcessive pressure in a radiator sufficient to cause unseating of saidgasket,

said lock ring providing means securing said gasket in integral assemblywith said cap to permit the cap, spring, back-up ring and gasket to beengaged on and removed from a filling neck seat as a unit,

an auxiliary valve member mounted on said back-up ring and said gasketadapted to open when the fluid in the radiator is cooling permittingfluid flow from the surge tank to the radiator, and

means on said cup-shaped cap for securing the cap with a tubular fillingneck of a radiator.

3. In a closure cap structure for attachment to a a generally cup-shapedcasting itself having a fluid nipple being integral with the castingextending outwardly from its side wall for connection with a surge tank,

a spring disposed inside of the cup defined by said casting,

a ring-shaped diaphragm mounted in the cup on said from the side wall ofthe cup and with said diaphragm being adapted for sealed engagement onits underside with a tubular filling neck,

means secured with the open end of said cup securing the diaphragm inassembly with said cup, the diaphragm being movable out of contact witha filling neck upon the development of excessive pressure in a radiatorpermitting fluids to be exhausted through the gap between the diaphragmmargin and the side wall through the cup and the nipple,

spring and having an outer diaphragm margin spaced 10 an auxiliary valvemember mounted on said diaphragm from the side wall of the cup and withsaid diagasket for permitting fluid flow through the cup into phragmbeing adapted for sealed engagement on its a radiator as fluid pressuretherein drops below a underside with a tubular filling neck,predetermined level, means secured with the open end of said cupsecuring a series of lugs extending radially outwardly of an thediaphragm in assembly with said cup, exterior wall of said casting forsecuring the casting the diaphragm being movable out of contact with awith a filling neck,

filling neck upon the development of excessive presthe nipple and thelugs being formed integral with the sure in a radiator permitting fluidsto be exhausted casting, through the gap between the diaphragm marginand an annular groove provided in the exterior wall of the the side wallthrough the cup and the nipple to a casting beneath said lugs, and surgetank, a gasket secured in said annular groove for fitted an auxiliaryvalve member mounted on said diaphragm sealed engagement with a fillingneck for a radiator. gasket closed when under high pressure conditions6. The combination of claim 1 further characterized but open when theradiator fluid cools, by said cap comprising,

means on said casting for securing said casting with a filling neck of aradiator,

said diaphragm comprising a ring-shaped diaphragm gasket having anintegral central collar with a groove on an extension surface of thecollar, and

a rigid back-up ring having its inner margin engaged in said groovesecuring the gasket and back-up ring in unitary assembly.

4. In a closure cap structure for attachment to a tubular filling neckfor an internal combustion engine radiator,

a generally cup-shaped casting itself having a fluid nip le beingintegral with the casting extending outwardly from its side wall forconnection with a a casting with the nipple extending outwardly of theside wall of the casting,

the casting having an annular flange about its exterior Wall surface,

a sealing gasket mounted beneath said annular flange on the exteriorwall surface of the casting,

said means comprising a ring shaped retainer cup mounted on top of saidannular flange and having a series of lock tabs secured beneath fillerneck tabs at its outer margin thereby securing the components of the capstructure in sealed assembly with said tubular filling neck.

7. The combination of claim 1 further characterized by said capcomprising,

surge tank, a casting with the nipple extending outwardly of an a springdisposed inside of the cup defined by said exterior wall surface of thecasting,

casting, said means comprising a series of lugs, a ring-shaped diaphragmmounted in the cup on said the nipple and the lugs being formed integralwith the spring and having an outer diaphragm margin spaced casting,from the side wall of the cup and with said diaphragm a sealing gasketmounted beneath said lugs on said being adapted for sealed engagement onits underside with a tubular filling neck,

means secured with the open end of said cup securing the diaphragm inassembly with said cup, the diaexterior wall surface for engagement on aradiator filling neck. 8. In combination, a closure cap structure and aninternal combustion engine radiator having a tubular filling neck withthe closure cap structure thereon and with a surge tank having a fluidlevel overlying the radiator,

hragm being movable out of contact with a filling neck upon thedevelopment of excessive pressure in a radiator permitting fluids to beexhausted through the gap between the diaphragm margin and the side wallthrough the cup and the nipple to a surge tank,

said cap structure including a generally cup-shaped casting seated onsaid neck and having a fluid nipple an auxiliary valve member mounted onsaid diaphragm extending outwardly from its side wall in overlyinggasket for permitting fiuid flow through the cup in spaced relationabove said neck and connected with a radiator as fluid pressure thereindrops below a said surge tank,

predetermined level, a compression spring disposed inside of the cupdefined means on said casting for securing said casting with b id i afilling neck ofaradiator, a pressure valve including a diaphragmcomprising said diaphragm comprising a ring-shaped diaphragm back-updiaphragm ring engaged on its top side with gasket, said spring andhaving a diaphragm gasket on its a back-up ring and a bushing securingsaid diaphragm underside for movement with said back-up diaphragm gasketand said back-up ring in assembly together, ring into and out ofengagement with said tubular said auxiliary valve member being mountedon said filling neck,

bushing. a lock ring secured with the side wall defining the open 5. Inaclosure cap structure for attachment to a tubular end of said castingholding the diaphragm on said filling neck for an internal combustionengine radiator, casting when said cap structure is detached from agenerally cup-shaped casting itself having a nipple said neck,

extending outwardly from its side wall for connection said cap structurewhen secured in assembly with said with asurge tank, neck having itsouter margin spaced axially from a spring disposed inside of the cupdefined by said said lock ring when said diaphragm is seated on saidting, neck and when said diaphragm is unseated from a ring-shapeddiaphragm mounted in the cup on said said neck upon the development ofexcessive presspring and having an outer diaphragm margin spaced sure inthe radiator,

said diaphragm having its outer margin spaced from the side wall of saidcasting permitting fluid flow therebetween into the cup and then throughsaid fluid nipple,

an auxiliary valve member mounted on said diaphragm closed during hightemperature periods of operation of the combination but open as theradiator fluid temperature drops permitting fluid flow from the surgetank to the radiator, and

means on said cup-shaped cap securing the casting in sealed assemblywith the tubular filling neck of said radiator.

9. The combination of claim 8 further characterized by said auxiliaryvalve member being suspended from said diaphragm by a wobble pin.

10. In a closure cap structure for attachment to a tubular filling neckfor an internal combustion engine radiator,

a generally cup-shaped cap itself having a fluid nipple extendingoutwardly from its side wall and with the cap and the nipple comprisinga one piece casting,

an annular axially facing cup shoulder at an open end of the cup-shapedcap,

a spring disposed inside of the cup defined by said cup-shaped cap,

a back-up ring mounted in the cup having an outer ring margin spacedfrom the side Wall and axially confronting said cup shoulder with saidspring engaged against said ring and with said ring having a gasket onits underside for engagement with a tubular filling neck,

a lock ring secured with an inside wall of the open end of said capspaced from and axially confronting said cap shoulder with said back-upring and said gasket being movable axially between said ring and saidcap shoulder upon the development of excessive pressure in a radiatorsuflicient to cause uuseating of said gasket,

said lock ring providing means securing said gasket in integral assemblywith said cap to permit the cap, spring, back-up ring and gasket to beengaged on and removed from a filling neck seat as a unit,

an auxiliary valve member mounted on said back-up ring and said gasketadapted to open when the fluid in the radiator is cooling permittingfluid flow from a surge tank to the radiator, and

lugs provided on a radially outwardly facing Wall of said cup-shaped capand provided as a part of said one piece casting for securing the capwith a tubular filling neck of a radiator.

11. The structure of claim 10 further characterized by the castinghaving an annular flange about its exterior Wall surface,

a sealing gasket mounted beneath said annular flange on the exteriorWall surface of the casting,

said means comprising a ring shaped retainer cup mounted on top of saidannular flange and having a series of lock tabs secured with said lugsthereby locking the components of the cap structure in sealed assemblywith said tubular filling neck.

References Cited by the Examiner UNITED STATES PATENTS 2,701,030 2/55HaZeltOn 2204O 2,860,656 11/58 Eshbaugh 22044 2,873,794 3/59 Stromberg1234l.27 3,067,908 12/62 Graham 220-44- THERON E. CONDO'N, PrimaryExaminer.

GEORGE o. RALSTON, Examiner.

1. IN COMBINATION, A CLOSURE CAP STRUCTURE AND AN INTERNAL COMBUSTIONENGINE RADIATOR HAVING A TUBULAR FILLING NECK WITH THE CLOSURE CAPSTRUCTURE THEREON, SAID CAP STRUCTURE INCLUDING A GENERALLY CUP-SHAPEDCAP ITSELF HAVING A FLUID NIPPLE EXTENDING OUTWARDLY FROM ITS SIDE WALLIN OVERLYING SPACED RELATION ABOVE SAID NECK, A VENTED SURGE TANKCONNECTED WITH SAID FLUID NIPPLE HAVING FLUID OVERLYING THE RADIATOR, ANANNULAR CUP SHOULDER AT AN OPEN END OF THE CUPSHAPED CAP, A SPRINGDISPSOED INSIDE OF THE CUP DEFINED BY SAID CAP, A BACK-UP DIAPHRAGM RINGENGAGED ON ITS TOP SIDE WITH SAID SPRING AND HAVING A DIAPHRAGM GASKETON ITS UNDERSIDE FOR MOVEMENT WITH SAID BACK-UP DIAPHRAGM RING INTO ANDOUT OF ENGAGEMENT WITH THE TUBULAR FILLING NECK, A LOCK RING SECUREDWITH THE SIDE WALL DEFINING THE OPEN END OF SAID CAP AXIALLY SPACED FROMSAID CAP SHOULDER WITH SAID BACK-UP RING AND SAID DIAPHRAGM GASKET BEINGMOVABLE AXIALLY BETWEEN SAID DIAPHRAGM RING AND SAID CAP SHOULDER UPONTHE DEVELOPMENT OF EXCESSIVE PRESSURE IN HE RADIATOR SUFFICIENT TO CAUSEUNSEATING OF SAID DIAPHRAGM GASKET FROM SAID FILLING NECK PERMITTINGFLUID FLOW BETWEEN THE OUTER MARGIN OF SID BACK-UP DIAPHRAGM RING ANDTHE SIDE WALL OF THE CUP INTO THE CUP AND THEN THROUGH SAID FLUID NIPPLEINTO SAID SURGE TANK, SAID LOCK RING PROVIDING MEANS SECURING SAIDDIAPHRAGM GASKET IN INTEGRAL ASSEMBLY WITH SAID CAP TO PERMIT THE CAP,SPRING, DIAPHRAGM RING AND DIAPHRAGM GAKSET TO BE ENGAGED ON AND REMOVEDFROM AW FILLING NECK SEAT AS A UNIT, AN AUXILIARY VALVE MEMBER MOUNTEDON SAID BACK-UP DIAPHRAGM RING AND SAID DIAPHRAGM GASKET ADAPTED TO OPENWHEN THE FLUID IN THE RADIATOR IS COOLING PERMITTING FLUID FLOW FROM THESURGE TANK TO THE RADIATOR, AND MEANS ON SAID CUP-SHAPED CAP SECURINGTHE CAP IN SERALED ASSEMBLY WITH THE TUBULAR FILLING NECK OF SAIDRADIATOR.